Five years ago, Ukraine's Orange Revolution was hailed as a new start for a country that had begun to look west towards the European Union and Nato. But as voters prepare to go to the polls next Sunday in the first presidential election since they cast out the country's Soviet-era leadership, Europe's most famous colour-coded reform movement seems to have run out of steam.

Both of the front-running candidates in the poll have indicated that firmer ties with Russia, whether for pragmatic or ideological reasons, will be a priority. The poll will thus ring the death knell for a pro-western revolution that degenerated into a morass of political infighting, compounded by economic crisis.

Leading the polls is Viktor Yanukovych, a former prime minister whose initial victory as the Russia-backed candidate in 2004 sparked allegations of a rigged vote. His only serious rival is Yulia Tymoshenko, the prime minister and Moscow's new favoured candidate. President Viktor Yushchenko, hero of the Orange Revolution, now has an approval rating below 3%. Last week he accused Yanukovych and Tymoshenko of comprising a "single Kremlin coalition", such was their joint desire for warmer relations with Moscow.

Yanukovych is expected to garner 33.3% of the vote, according to a mid-December opinion poll by Ukraine's R&B Group, with Tymoshenko scoring 16.6%. A collection of 16 candidates, including Yushchenko, are expected to split 40% of voters between them, while more than 10% of the electorate remain undecided. A second round between the two frontrunners is widely expected – it is scheduled for 7 February – with Yanukovych likely to be in pole position.

Whether Yanukovych or Tymoshenko wins, the goal of Nato membership, still aspired to by Yushchenko, is almost certain to be abandoned. Officials close to the Kremlin have said that Nato membership for Ukraine and Georgia was seen as an "existential threat" to Russia.

Yanukovych last week repeated his long-held stance that he would take Ukraine off the path to Nato membership. "Ukraine was and will be a non-aligned nation, as it is now," he told Ukraine's Komsomolskaya Pravda.

While he also said he would keep the country out of the Collective Security Treaty Organisation, a Moscow-led defence grouping, he would push to join the economic union being formed by Russia, Kazakhstan and Belarus. Russia has lately favoured economic integration, and pushed for the rouble to become a regional reserve currency, as a means of spreading its influence.

Russia has not openly backed a candidate, unlike in 2004 when it threw all its weight behind Yanukovych. "They don't want to be in a situation like 2004, where they put all their eggs in one basket and lost Ukraine for some years," said Alexander Rahr, head of the Russia/Eurasia programme at the German Council on Foreign Relations.

Yanukovych is understood to have angered Moscow by supporting Ukraine's attempt to join the EU. But Tymoshenko has become the unexpected hero of the Kremlin, after tempering the anti-Russian stance that was a hallmark of her 2004 campaign and early premiership. While remaining avowedly pro-EU, she has built a pragmatic alliance with Vladimir Putin, the Russian prime minister. The two very publicly ended the drawn-out gas dispute between the two countries last winter and were credited with avoiding a repeat this year. Tymoshenko now calls the Orange Revolution "a revolution of lost opportunities".

The near annual gas dispute first erupted after the inauguration of the Yushchenko government, when Russia suddenly hiked gas prices on the eve of 2005, eager to stop subsidising a neighbour that was no longer a de facto vassal state. Political punishment came in the form of increasingly aggressive rhetoric over the status of Crimea, an autonomous region on Ukraine's Black Sea coast that used to form part of Russia. That rhetoric is taken seriously after the Russian-Georgian war over South Ossetia in summer 2008.

Yushchenko – who is sixth in the vote with an expected 3.8% – has lost his traditional support in the country's western regions to Tymoshenko and lesser-known candidates. Yanukovych has retained his popularity in the Russian-speaking east and south.

In Ukraine the words of the day on Russia are "pragmatism" and "balance". "Both [Yanukovych and Tymoshenko] will find a balance of interests between Russia and the west," said Volodymyr Fesenko, of the Kiev-based Penta Centre for Applied Political Studies.

The election comes as Ukraine wallows in a financial crisis that saw the economy shrink by 15% last year. The country is due to repay £12.5bn of foreign, mainly corporate, debt this year, and the hryvnia is down 50% since the crisis began. Kiev became one of the few governments to appeal to the International Monetary Fund for emergency aid, taking more than £10bn in loans. The IMF has frozen delivery of some tranches, citing a lack of internal reforms.

"The enthusiasm of the west vanished very quickly after 2004," notes Rahr. "We don't know what to do with Ukraine. We know what we don't want – we don't want Ukraine to become part of Russia again. But that's not enough, and that's our strategy."